Although the present invention can be adapted to providing a terminal for buried communication lines of various types, the invention will be described with relation to its use as a terminal for buried telephone lines.
In the installation of buried telephone lines, there is a need for a terminal that is completely reliable in withstanding adverse weather conditions. This includes protecting the buried telephone cable installation from water damage, including floods. Hot weather conditions prevalent in desert areas also can be a problem for buried telephone line terminals. Digital transmission, in particular, requires a dry environment inside the telephone terminal housing.
There is also a need for a terminal for buried cable which is not subject to aging or deterioration and which can be immune not only to weather conditions described above, but also to salt spray, acid or alkali soils, insects, fertilizers, insecticides, or other hostile environments.
One prior art terminal housing comprises a buried metal box. Loop cable passed to the inside of the box is taped to keep out moisture. This arrangement has proven unsatisfactory, especially because of its short useful life and the additional cost of phone installers to re-install the lines when problems arise in the field.
In addition to protecting telephone line installations from weather conditions and other hostile environmental conditions, an underground terminal also should reduce installation time and cost initially and as further service lines are later connected at the terminal site. Simplicity in the installation procedure is particularly useful for service wires inasmuch as each service wire installation may, over a period of time, be the responsibility of different service personnel.
The present invention provides a terminal for underground communication lines, such as telephone lines, in which the installation at the terminal is completely sealed from the environment. The invention is particularly characterized by being airtight and watertight to the extent that it meets the most stringent of industry imposed standards for long-term protection against water damage, heat, and other environmental hazards described above. The terminal also is easy to install, can be manufactured at a reasonable cost, and facilitates ease of later installation of service wire at the terminal site.